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,~ The Escalante Wetlands are a relatively recently phenomena in the river valley (post 1900; Cooper and Severn, 1994). The wetlands hydrology evolved in a series of old abandoned meander bends after 1937 based on aerial photography (Cooper and Severn, 1994). These meander bends have remnant depressions ~of the old river bed which may capture and store windblown snow in the late winter or early spring. In April and May, while the river is rising, the melting snow and spring precipitation adds to the surface water in these depressions and the ponded water surface expands. The wetlands become excellent habitat for migratory waterfowl. As summer ensues, the wetlands Megan to diminish through evaporation and groundwater flow to the old river channel alluvium. There was no overbank flow from the river to the wetlands in 1993. By late fall, the wetland ponds usually decrease to a relatively small surface water area which is densely vegetated with healthy cattails and bulrush. The wetlands water surface area decreases throughout the summer despite being fed by seepage from the sloping bluffs to the east. This groundwater seepage inflow to the v~Tetlands is irrigation seepage water from the cultivated ranch land to the east. High summer water temperatures in the wetlands increase the evaporation losses and groundwater seepage draining the wetland ponds may increase as the river level drops. The irrigation groundwater seepage from the bluffs is insufficient to sustain a constant wetland water surface throughout the year. Historical observations have indicated that in some years the ponded water in the wetlands may virtually disappear by mid- fall. This was substantiated by observations of cracks in the bottom muds by Cooper and Severn (1994; p. 64-5) who related that the "...wetland had been dry, mostly likely over the past winter." 5